Too often it happens that gods loosen and is displaced, or fall off during transport. Sometimes this results in fatal consequences with loss of lives, while other times there are only material damages and loss of values. Badly secured loads represent, in any case, an undesired risk and should be fought with all means. Good training of the drivers is most important, next frequent controls and powerful response to misconducts. The road traffic act gives the driver a complete and independent responsibility that the vehicle is being properly loaded. Still it often occurs that a load loosens or is being displaced, so that gods fall off or that the vehicle tilts. Load is today, for example, secured by means of fasteners, such as ratchet straps, chains, wires, ropes, and bars or similar. The fasteners are usually of a type which can be tightened after they are adapted around/to an object to be fastened, secured or anchored.
Even if the load is secured by fasteners, as mentioned above, it could during transport be displaced due to movements or that the load has “yielded”, so that the fasteners are slacked. It is thus a great need for reliable systems which can provide an early warning of a possible dangerous situation, which thus can be avoided. This is important for preventing accidents with loss of lives and loads at transport, among others, on road, at sea, rails or in the air.
There are known different systems for this object.
From EP 1467193 it is known a system for monitoring the tensile stress in a belt around an object. In EP 1467193 there is used a force sensor to measure the tensile stress.
From U.S. Pat. No. 6,357,978 it is known a load indicator for indicating tensile stress, especially in a ratchet strap. U.S. Pat. No. 6,357,978 describes primarily a visual indicator.
GB 2255109 describes a system for measuring load by means of mechanical metering of the load.
Prior art technique is switch-based, which results in that a continuous monitoring is not possible, but will be an “on” or “off” measurement which can result in that a warning is provided too late in a critical situation. Switch-based solutions further have no plain way to change the setting for the warning of a critical situation, as this must be done mechanically. Known solutions neither exhibit nor suggest measuring principles which are usable for different types for fasteners.